In the video, Brian cleans the filter on a wall-mounted ductless mini-split. Clean filters keep the unit efficient and the air clean.

Video by Brian Huie on YouTube. Watch on YouTube

How often: Monthly (every 2 weeks in peak season)
Video: 18 seconds

How often should you clean mini-split filters?

Trane, part of Mitsubishi Electric Trane, says as often as every two weeks during peak heating or cooling season, and about once a month with lighter use. Efficiency Vermont suggests checking about monthly, and more often with pets or heavy use. The owner's manual sets the exact schedule.

How do you clean them?

Turn the unit off with the remote or wall control and open the front panel.
Lift the filters out gently so dust does not fall off.
Vacuum with a brush attachment on low suction. If they need more, rinse them in lukewarm water; a sticky filter can be washed with mild soap and a soft nylon brush.
Let the filters dry completely, slide them back in, close the panel and turn the unit back on.

Safety notes

Turn the unit off before opening it.
Use low suction, since strong suction can damage the filter, and keep any small deodorizing filter dry.
Avoid bumping the metal fins when reinstalling the filters.
Keep the outdoor unit clear of leaves and snow, using a brush or broom rather than a shovel.

Seattle-area notes

Seattle City Light's general advice applies: check filters and schedule annual maintenance.

When to call a pro

Trane recommends professional maintenance at least once a year, or twice a year for systems that both heat and cool, including cleaning the units and checking for refrigerant leaks.

Sources

Checked October 2026. Manufacturer instructions for a specific model come first. General information, not a substitute for a licensed professional.

From the Home Care Advice by Brian Huie, a principal broker and Realtor with Compass in Seattle.

Home Care Advice

How to clean mini split filters